package com.appspot.urlheap.servlets;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.google.appengine.api.users.User;
import com.google.appengine.api.users.UserService;
import com.google.appengine.api.users.UserServiceFactory;

public class AuthFilter implements Filter {

	public void init(FilterConfig config) throws ServletException {
	}

	public void destroy() {
	}

	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
		UserService userService = UserServiceFactory.getUserService();
		User user = userService.getCurrentUser();
		if (user == null) {
			String url = ((HttpServletRequest) request).getRequestURL().toString();
			String query = ((HttpServletRequest) request).getQueryString();
			if (query != null && query.length() > 0) {
				url += "?" + query;
			}
			((HttpServletResponse) response).sendRedirect(userService.createLoginURL(url));
			return;
		}
		chain.doFilter(request, response);
	}
	
}
